octeontx2-af: mcs: Config parser to skip 8B header

commit 66af26e4163126d277d950f73bcf91ac006960bb from
git@git.assembla.com:cavium/WindRiver.linux.git

When RPMX_CMRX_CFGX.rx_ts_prepend=1 (for ptp), rpm append 8B
timestamp header for all RX traffic. This patch configures MCS
parser to skip this 8B header while parsing the packet headers.

Change-Id: I0c6ade127bef37d2da7115e79369ab0fb87d7312
Signed-off-by: Geetha sowjanya <gakula@marvell.com>
Reviewed-on: https://sj1git1.cavium.com/c/IP/SW/kernel/linux/+/91961


Tested-by: sa_ip-sw-jenkins <sa_ip-sw-jenkins@marvell.com>
Reviewed-by: Sunil Kovvuri Goutham <sgoutham@marvell.com>
[WK: for rvu_cgx.c, adjust codes from rvu_mbox_handler_cgx_ptp_rx_enable()/
 rvu_mbox_handler_cgx_ptp_rx_disable() to rvu_cgx_ptp_rx_cfg()
]
Signed-off-by: Wenlin Kang <wenlin.kang@windriver.com>